Cylinder grinder



Oct. 26',1.1.926. I,

- J. BRANDSTETTER CYLINDER GRINDER Filed March 30 1925 Ill-ll l 7 /Bran/j-SE l" www.

Patented Oct. 26, 1926.

.U Ni T E ST AT ES JOSEF niaannsrnrrnn,

afi-senr eric-Ei or CHICAGO, rLnINoIs.

CYLINDER GRINDER.

appncation'iea March 3o, 1.925. sriai no. 19,257.

lsheets of abrasive material, wliioh can readily be adjusted as'to its effective diameter, which will cause the adj ustmentsin diameter' to beK made equally throughout the length ofthe grinding member, which will have, its adjustment latched in any adjusted position, and which'will permitthe grinder to befrotated by a shaft disposedat an angleV to the bore'which is to be ground.

Still further and also more detailed Olojects will appear fromthe following specification' and from the accompanying drawings, in which- Fig. l is a perspective Viewl of a grinder embodying my invention, showing this before the sheet of `abrasive material is attached to the same( 2 is a central and longitudinal section through the same taken along the line 2-2 of Figf. d

Fig.` 3 is an enlarged plan view of the` same grinder, showing this as it appears with` a sheetpo'f abrasive material clamped' to it. l

Fig. 4 is a vertical section taken along the line/4 4 of Fig. 3 to show the means for simultaneously expanding the tubular member ot' the grinder and for equalizing the expansion at both ends of the same.

Fig. 5 is anenlarged'perspective view of `theupper expanding wedge o'flfig. l and Y the llatch'ing spring secured tothe same.

showing anotherl arrangement of the eX- panding and, expansion-equalizing means.

In the illustrated embodiment, my bore grinder includes a tube l of a resilient material, which Amay be made, for example, of

g .l the grade ofY iron commonly` employed for This tube. has the general piston rings.` A form of a hollow cylinder split longitudinally along one side so as'to aiidord agap of sufficient width to .permit expanding means to be interposed vloetweenthe opposed edges of the gap, and also to pro-vide room for means which clamp one edge ofan abrasive'sh'eetto the tube. `With these objects in i mind,A l ,desirably provide the'tube with inwardly; directed webssand' disposed at airai'igle to each `other and extendin ldgiV tudinallyf of thetube opposite" sides fait downward screwing;

the gap. These webs 2 and 3 have their opposed fa`c'es`-be`veled adjacent to each end so as to cause the g-"ap to widen towards 'each end of theftube as shown in Fig. l. Inserted between'these beveled gap' walls at'opposite ends of the tube are a pair of wedges 4 'and 5, each of which preferably' corresponds in taper to the said beveling, thereby affording a relatively long bearing between each wedge and the two webs at opposite sides thereof. i

With the wedges o'fsuitable width, it` will be obvious from Fig'. l that an' approaching moteinent of the two Ywedges will widen the gap, thereby expanding thel resilienttube, while 'd a separational` movement ot` the `wedges `wili permit the resiliency of the tube to contract its diameter. To effect such an expansion, I provide expanding means which preferably actuateboth wedges simultaneously. yThese means are shown in Fig. 4 as consisting of'a rod 6 'extending slidably through longitudinal `bores'in the wedges and 5, xthis rod havings at its lower end a head 7 adapted to 'exert an vupward thrust on the lower wedge aand having an upper portion threaded toV rita knu'rlcd nut 8 which bears against"v the top ,of the upper' wedgeV 4. Thusarranged, a downward screwing of the nut 8 will slierten the length o'fthe'rod portion` 6 between the two-wedges and hence will cause the wedges to approach each other. f d i However, this approaching might not be symmetrical vwith respect to the "length lof the tube, so that one end ,of thetube would d d y be expanded more than the other;` To avoid Fig. 6 .is a section similar to Fig. 4, buty this, if alsoprovide means for, equalizing the expanding faction ,of the two wedges. Such meansmay consist of awasher 9 loosely housing l a medial portion of thefrod 61 and socleted in recesses inw then/'ebs' 2 and 3 which, preventy theywash'er `'from moving longitudinally o'f the gap, and `a pair `of compression springs l() and 11 interposed respectively betweenthe washer 9V` and the` two wedges ;4`an"d 5. `With the washer and the'two springs thus interposed between the wedges, and with the springs offequal effective strength, the washer will prevent each spring from` moving:longitudinally and the springs will equalize the effective thrust eX- erted by the downward screwing of the' nut d, thereby causing the" to move equally towards eac m her during such interese, if the ma a Y equally in both directions from the centrally located washer. Consequently, the expanding and contracting will always be the same at both ends of the tube, thereby affording Vva cylindrical outer tube surface on which the abrasive sheet can bear. This sheet 12 only needs to be fastened to a single one of the webs, namely the web at the same side of the gap toward which the tube is rotated when the grinder is in operation. TvVith this in mind, I may employ a single clamping plate 14 fastened by screws to the web 2 and adapted to have one end of the abrasive sheet 12 clamped between this plate and the web 2, while the other end portion 13 of the abrasive sheet can extend loosely into the gap as shown in Fig. 8, thus permit-ting t-he sheet to be drawn tautly around the cylindrical outer surface of the tube during the grinding operation.

To prevent the nut 8 from being jarred out of its adjustment, I desirably provide suitable latcliing means. These are shown in Figs. 1 and 5 as comprising a latch spring 15 fastened at its base end to the wedge 4 and having a V-sectioned free end adapted to engage any one of a number of longitudinal A grooves on the stem of the thumb nut 8.

'Io rotate the grinder, I preferably provide ashaft connected to the tube in such a manner as to permit the shaft to tilt con- Y siderably with respect to the axis of the tube.

Thus, Figs. 2 and 3 show a swiveling shaft 16 extending diametric of the tube and substantially at right angles to the medial plane of the said gap into oppositely disposed inner bosses 17 on the tube, this swiveling shaft 16 being freely rotatable in the said bosses. The actuating or drivev shaft 19 is threaded into a fork 18 pivoted tothe middle of the Vswiveling shaft 16 (the connection being shown in Fig. 3' as made by means of a spring Cotter 20), thereby permitting the actuating shaft to tilt after the manner shown in Fig. 2, while a loose soclreting of Y the ends of the swiveling shaft 16 in the tilting.

bosses 17 permit the actuating shaft to tilt in a plane at right angles to the aforesaid 'Io Vfacilitate the mounting of thel swiveling shaft 16, I desirably malte this in the form of a simple'rod which' can be slidably inserted from either side of the tube two bosses 17. i

Vand which is locked against longitudinal Vmovement in both directions by a pair of spring cotters 21 respectively adjacent to the To maintain effective bearings between the wedges and the beveled web edges, I desirably make the lateral faces ofV each web embodimentshapes and arrangements of the various of a V-shaped section and malte the angle of the V-formation somewhat larger than the angle between the free end and the outer face portion of the adjacent web on the tube. This difference in the angles limits the engaging portions to a line at the extreme inner edge of each web and the bottom of the V-shaped groove in the adjacent wedge edge, and also permits this linear engagement to be maintained while the diameter of the tube is varied during the adjusting of the wedges.

It will be ob-viousfrom the above that the grinder of my invention is quitelsimple and inexpensive in construction, that its eifective diameter can readily be varied by the adjusting nut 8, that the springs 10 autopermit the tube to be rotated by means ofV a shaft disposed at a considerable angle to the axis of the bore which is to be ground, thereby permitting my grinder to be em ployed where adjacent portions of the engine or the like would interfere with the use of a driving shaft extending coaxial with the cylinder bore.

However, while I have illustrated and described the grinder of my invention in an including highly desirable parts, I do not wish to be limited tol the details of the construction and arrangement thus disclosed, it Lbeing obvious that the same might be inoditied in many ways without departing' either from the spirit of my invention or from the appended claims.

For example, the expanding means might comprise a rod 22 having eiid portions'provided respectively with right-hand and left hand threads and respectively threaded into the wedges 4 and 5, so that the wedges will be positively moved either towards or away from each other according to the direction in which the rod is rotated, without requiring springs for moving them in one direc tion. In this embodiment, as shown in Fig. 6, the centralizing collar 23 would be fast on the rod 22, this collar being likewise restricted against axial movement by the walls of the recesses of the webs 2 and 3, while the rotating of the rod may be eected through a knob 24 riveted to the rod 22.

I claim as my invention 1. A bore grinder comprising an expansible tube split on one side to afford a gap between two edges extending longitudinally of the tube, means for securing an abrasive gap and respectively at opposite ends of the gap,

2. A bore grinder comprising an expansible tube split on one side to afford a gap between two edges extending longitudinally of the tube, means for securing an abrasive sheet to the exterior of the tube, and expanding means including two simultaneously movable wedges disposed in the said gap and respectively at opposite ends of the gap, means for moving the wedges towards each other,l and spring means for moving the wedges away from each other.

3. A bore grinder comprising an expansible abrasive-carrying tube y having as its exterior a cylindrical surface interrupted at one side by a gap extending longitudinally of the tube, the tube having at the opposite edges of the gap a pair of webs extending inward of the tube, the two webs having their opposed end portions beveled away from each other, a pair of wedges respectively disposed between the beveled end portions at opposite ends of the tube, and means for ymoving the wedges in unison towards or away from each other.

A grinder as per claim 3, in which each wedge has lateral web-engaging portions inclined to correspond to the angle between the adjacent web ends.

5. A bore grinder as per claim 3, in which each side of each wedge is V-shaped in a section transverse of the tube and has the bot-tom of its V-shaped formation engaging the inner longitudinal edge of the adjacent web.

6. A bore grinder as per claim 8,I in which each side of each wedge is V-shaped in a section transverse of the tube and has the bottom of its V-shaped formation engaging the inner longitudinal edge of the adjacent web, the angle between the faces of the said V-shaped formation being greater than the angle between the two adjacent faces of the adjacent web of the tube.

7. A grinder as perclaim 3, including a clamping member secured to the tube within the gap radially outward of the wedges and of the wedgemoving means, and adapted to 1plamp onel end of an abrasive sheet to the tu e.

8. A grinder as per claim 3, in which each wedge has lateral web-engaging -portions inclined to correspond to the angle between the adjacent web ends, the said angles being equal for both wedges.

9. A bore grinder comprising a resilient and diametrically expansible abrasivecarrying tube split on one side longitudinally of the tube, means disposed at the gap formed by the said split for adjustably expanding the tube, a thrust element disposed at the gap medial of the length of the tube, a pair of ywedges inserted in the gap at opposite ends thereof, a threaded rod extending through the two wedges and adapte'd to move the 'wedges toward each other,

and a pair of compression springs respeca tively interposed between the thrust element and the two wedges for moving the wedges away from eachother.

10. A bore grinder comprising anv expansible and abrasive-carrying tube longitudinally split along one side to afford a gap, two means associated with the opposite ends of the gap for expanding the gap at both ends thereof, means for simultaneously Yoperating the Ltwo expanding means, and

means for latching the said operating means.

Signed at Chicago, Illinois, March 26th, 1925.

JOSEF BRANDSTETTER. 

